Ergonomic Risk Prioritization of Work-Related Musculoskeletal Disorders in Lead-Acid Battery Manufacturing: A Cross-Sectional and Observational Study

Objectives : This study aimed to investigate the prevalence and distribution of Work-related musculoskeletal disorders (WMSDs) among lead-acid battery manufacturing workers and to identify high-risk tasks and body regions through integrated epidemiological and ergonomic assessments, thereby establishing priorities for ergonomic intervention. Methods: We conducted a cross-sectional survey among 2,418 frontline workers from 10 lead–acid battery manufacturing enterprises in Jiangsu Province, China, using the Chinese Musculoskeletal Questionnaire (CMQ). Multivariable logistic regression was used to examine individual and work-related factors associated with WMSDs. Key production tasks were additionally assessed using video-based observation, with ergonomic hazards screened by the Swedish ergonomic hazard identification method and postural load quantified using the Rapid Upper Limb Assessment (RULA). Results: The overall 12-month prevalence of WMSDs was 51.61%. The lower back and wrist/hand were the most frequently affected regions, followed by the shoulder and neck, with higher neck and shoulder prevalence among female workers. Manual handling of heavy loads and highly repetitive operations were associated with increased odds of both low back and wrist/hand WMSDs, whereas adequate rest time and physical exercise showed protective associations. Using the Swedish checklist, hazards were most frequently identified in the neck/shoulders/upper back (34/36 positions), upper limbs (29/36), and lower back (28/36). RULA classified 22/36 (61.11%) job positions as action levels III–IV, including 12/36 (33.33%) requiring immediate changes, indicating substantial postural load in key tasks. Conclusions: WMSDs impose a substantial burden in lead–acid battery manufacturing. Combining symptom surveillance with observational ergonomic assessment helps identify and prioritize high-risk tasks for targeted intervention, providing actionable evidence for workplace redesign and occupational health risk management in labor-intensive manufacturing settings.